The invention refers to a method and an arrangement for netwide call trace with various interfaces and protocol stacks of at least one call within a telecommunication network.
Intelligent telecommunication networks include networks for mobile communication being connected to fixed telephone networks. This is described in detail for example in the book xe2x80x9cMobilfunk und Intelligente Netzexe2x80x9d by Jacek Biala, Vieweg Verlag, Braunschweig/Wiesbaden, Germany 1996, ISBN 3-528-153024, and in respective standards and recommendations of international organizations as for example ITU (International Telecommunications Union) or others also mentioned in the above referenced book.
A Global System for Mobile Communication GSM is connected via a Gateway Mobile Services Switching Center GMSC to, for example, Public Switched Telephone Network PSTN, Public Land Mobile Network, Integrated Services Digital Network ISDN, Packet Switched Public Data Network PSPDN or other mobile networks as for example D1, D2 or E1 Networks in Germany. A PSTN comprises several switching which are connected with each other in or to build up connection between an optional number of users located at an optional number of geographical places within the network. The GSM comprises a Switching Subsystem SSS performs the call management as well as the subscriber adminstration. For this, the SSS includes a Home Location Register HLR, a Visitor Location Register VLR, an Equipment Identification Register EIR and an Authentication Center AC all being connected to an Mobile Services Switching Center MSC. Within one GSM there are many MSC connected with the allocated HLR, VLR, EIR and AC. Between the main components exist standardized interfaces also mentioned in the above referenced book and international standards and well know to a person skilled in the art.
For the network operator it is necessary to get knowledge of mistakes in the transmission path independent of the endpoints of the call. Up to now there exists no possibilty for a netwide trace call.
It is therefore the object of the invention to provide a possibility to perform a netwide trace call. This object is solved by a method and an arrangement according to the invention.
The method according to the invention comprises the following steps:
activating the intelligent agents IA by the central server (CS) together with a message comprising the a trigger (TN) to be call traced;
comparing the trigger number (TN) with the contents of the call establish messages of the calls running on the signalling channel (SC) by the intelligent agents (IA) and sending an establish message to the central server (CS) by those intelligent agents IA which have matched with the trigger number together with additional information (RL) about the detected connection between two switching points (SP) as well as at least the identification number of the intelligent IA;
sorting the messages and information (RL) by the central server (CS) sent by the intelligent agents (IA), removing redundant information and allocating the information to the respective section belonging to two switching points (SP) being connected together;
tracing all signalling data belonging to the detected call by the intelligent agents (IA) being involved in view of the matching of the trigger (TN);
detecting the call terminating by at least one of said intelligent agents (IA) and sending a call termination message to the central server (CS), forwarding of the message concerning the call termination to all the other intelligent agents (IA) being involved in the call trace; and
transmitting the recorded data to the central server (CS) and displaying of the data by the central server (CS) dependent on the different transmission layers in the telecommunication network.
The arrangement according to the invention for net wide call trace of at least one call within a telecommunication network comprises a central call trace server (CS) and local call trace intelligent agents (IA) between the switching points (SP) of the telecommunication network, said central call trace server (CS) being connected with all of said local call trace intelligent agents (IA) and comprising a call trace managing means with a call trace graphical user interface (GUI) and an interface connected to said intelligent agents (IA), and said intelligent agents (IA) comprise an interface to the central server (CS) and an intelligent call trace unit (IU). The central server (CS) and intelligent agents (IA) are adapted to communicate with each other and to perform the following operations:
activating the intelligent agents IA by the central server (CS) together with a message comprising the a trigger number (TN) to be call traced;
comparing of the trigger number (TN) with the call establish messages the calls running on the signalling channel (SC) by the intelligent agents (IA) and sending an establish message to the central server (CS) by those intelligent agents IA which have matched with the trigger number together with additional information (RL) about the detected connection between two switching points (SP) as well as at least the identification number of the intelligent agent IA;
sorting the messages and information (RL) by the central server (CS) sent by the intelligent agents (IA), removing redundant information and allocating of the information to the respective section belonging to two switching points (SP) being connected together;
tracing all signalling data of the signalling channel (SC) by the intelligent agents (IA) being involved in view of the matching of the trigger number (TN) and transmitting the call relevant data to the central server (CS);
detecting the call terminating by at least one of said intelligent agents (IA) and sending a respective message to the central server (CS), forwarding the message concerning the call termination to all the other intelligent agents (IA) being involved in the call trace; and
transmitting the signaling data of the call from the intelligent agents (IA) to the central server (CS) and displaying the stored data by the central server (CS) dependent on the different transmission layers in the telecommunication network.
According to one important feature of the invention only a reduced set of necessary data are sent to the central server by the intelligent agents. In case that the central server requires more data, e.g. for enhanced result presentation, these data are sent by the intelligent agents upon request of the central server. This avoids the sending of unnecessary information and overload of the central server.